Solution:
Subterranean

Written by
Ken Olum

The first step is to figure what is going on. The arrow and "exit to
Miskatonic St" and the description of a human presence below ground
are supposed to clue the subway. The text at the front
is supposed to clue Davis Square station. 1984 is the year that the
red line extension was opened. Porter is the deepest station and is
supposed to be clued by "far, far beneath the ground". "headed for
the wilderness... a short trip" is supposed to clue the next station
outward, which is Davis.

At Davis Square there are tiles with pictures made by children on the
wall in the patterns shown, except that the different sets are
side-by-side rather than one atop another. There is a sign that says
"exit to College Avenue". The childrens' names are given on the
tiles, and the numbers give the position within the name to take a
letter (or in one case 2 letters). The letters for each set of tiles
make a word, and the words are